We cannot tell you an exact number, so please dont ask. There are too many variables in an engine, such as carb size, compression ratio, exhaust system, porting, etc. to give you this figure. A safe estimate on a stock engine is about a 10% gain.

Engine simulator software packages are a starting point, not the final answer. There are so many things that the simulator programs do not take into account, such as follower placement in relation to the lobe. Your head may be able to flow 0.500 lift, but your follower placement / size may only allow 0.400.

Adjustable cam gears (or sprockets) allow you to move your camshaft lobe center for better engine tuning. If you are racing your vehicle, you should have adjustable gears. If you have surfaced your head, or decked the block, you need adjustable gears.

Web Cam offers both hardwelded cams and billet cams for many applications. We believe that our hardwelding process is the best option in extreme racing conditions. We offer billet cams for people that do not want to send in their stock OEM camshaft for welding, and are not demanding as much from their engine. When you buy a billet camshaft, you will avoid the core charge.

A core charge is the charge for the original OEM camshaft. If Web Cam is going to hard weld or re-grind an original OEM camshaft, we need one to do the work on. We charge you for the original OEM camshaft, and will refund the charge when you return your original OEM camshaft to us (within 6 months). If you wish, you can send your original OEM camshaft in first, and we will do the work on your OEM camshaft, and you will not be charged a core charge. This will take a little longer, since we have to wait for your OEM camshaft to arrive to do the work.

OEM valve springs can only handle so much valve lift before they enter coil bind. This is where the spring has no more room to compress. In other cases, the OEM valve spring cannot control the valve properly, and valve float can occur. With a performance or racing valve spring kit, there are fewer coils (in most cases) and more room between the coils, allowing the spring to compress more, in turn allowing for more valve lift, while keeping the valve under control.

Web Cam does not advise reconditioning (re-grinding of the cam contact surface) of our tappets for re-use. Web Cam tappets undergo a proprietary heat treatment process and reconditioning can remove the hardened surface of the tappet. In the event the surface on which the cam-lobe makes contact is visibly free of wear and scuff-marks, then the tappet can be re-used with the same camshaft that it has been running against.

Web Cam valve shims can be ground as long as they are kept parallel and perpendicular to the outer diameter. "Professionally" lapping a shim or Blanchard grinding shims are acceptable options. Additionally, a device/fixture that has been designed to locate a shim to produce parallel surfaces that are perpendicular to the OD by way of a butt-grinding on a valve facer or similar equipment is also acceptable.

Many times this type of interference is created when the valves have been sunk into the head and the tips of the valves have been "excessively" ground (shortened) and thin shims are being used, to achieve recommended lash. In this condition Web Cam recommends either replacing the valve seats or using custom valves that are designed with the corrected overall length and the factory groove location. Web Cam does not advise retainer modification for this type of condition.

Web Cam has both standard and custom guides that allow for more clearance for these types of conditions. Web Cam also advises moving any guides already in place further into the head, when a retaining ring or a guide shoulder is not present. Be sure to check all clearances when moving the stock guide into the port. Bear in mind that a valve job will be required when altering the guide location. Web Cam does not advise modifying the retainer for this condition.

Web Cam recommends that all valve guide hole(s) prior to guide installation be free of gall-marks and are round and parallel. Professional inspection devices are required to perform these determinations. Additionally, Honing, reaming and or boring a valve guide hole may be necessary operations when a valve guide hole needs to meet this criterion. The following recommendation(s) are for any combination of bronze or cast guides and aluminum or cast iron heads.

.0015" to .0025" - Intake and Exhaust

Web Cam does not agree that an o-ring can allow for the necessary fit required to create optimum heat transfer and or fitment. Always consult with qualified professionals suited to inspect and repair your engine.

In any combination or the following: Black Diamond®, White Diamond® or Tensilite® valves, cast iron or bronze guides, Web Cam recommends the following ID clearances:

Intake: 0.0008" to 0.0012"Exhaust: 0.0011" to .00150"

Web Cam does not recommend clearances for Nitrous or blown applications. The recommendations above are offered in conjunction with the use of a thin film of Paste-Type, Molly-Based assembly lube, applied to the stem of the valve prior to installation.

Web Cam recommends honing the ID of guides prior to installation to a slip fit to the valve stem diameter, using the valve as a gage or a seat and guide machine pilot as your gage. Cast iron guides are easily reamed and Web Cam then recommends honing them to achieve a surface finish of RMS-32 or better. Bronze guides can be difficult to ream unless in well secured and accurately aligned conditions and preferably with the use of coolant. Web Cam recommends rigid type mandrel hones or diamond hones for controlled ideal results, when honing cast iron or bronze guides.

Web Cam only offers high quality long lasting valve stem seals. Web Cam believes that Teflon® and Viton® are the two best materials available for valve stem seals. Web Cam carries a line of Red-Viton® seals and offers black Viton® and Teflon seals as well. The only difference in the red and black Viton® is the physical outer seal dimensions.

All but specific titanium valve applications to be faced and or serviced. Web Cam strives for quality and durability when it comes to designing any valve. That being said, it should be noted that for titanium applications that are supplied by Web Cam with coated faces, Web Cam recommends not facing these valves. The special coatings on the face of these valves will enhance the durability of the valve face.

Tipping a valve to achieve factory stem protrusion can create an undesirable effect. Web Cam recommends that a trained and experienced professional determine the amount of material that can or should be removed.

Web Cam builds valvetrain system(s) based on a system approach. We evaluates cam profile(s) and given harmonics when engineering spring forces, heat treatment and materials for a given application. The weight of each component of a given system is as important at the cam dynamics and engine RPM(s). Web Cam recommends using the complete system approach when converting from titanium to stainless steel valves.

Lash caps are used for a series of conditions. Lash caps can be used to correct valvetrain geometry. They can be used to allow a greater wiping area for aggressive type cam profiles. They can also be used on titanium valves that are paired with a rocker arm. Lash caps are also used in some applications to adjust the valves. When using lash caps always make sure that there is ample clearance between the keepers and the cap. Web Cam recommends a minimum of 0.030" for this type of condition, unless the cap was designed to mate with the keepers.

Web Cam does not advise partial conversions on race bike and/or engines that have reached factory advertised service limits. In the event that your engine has reached or exceeded factory service limits, then we recommends installing a new complete valve spring kit and all new valves. However, on a low hour engines with apparent intake face recession and exhaust components that meet factory specifications, consider a Intake Only System, when performing necessary service. Always consult with qualified professionals suited to inspect and repair your machine.

Web Cam does not recommend making any changes that affect the valve spring contact areas. Modifications that do not affect the valve spring contact areas are allowable. However, each basewasher has been designed to a minimum cross sectional area, and any changes could adversely affect the strength of the basewasher. We recommend basewasher modifications only be performed by experienced engine builders.

Web Cam recommends that when seats are removed, the counter bore in the head is then machined to produce a round accurate and well finished counter bore. We offers the follow valve seat installation interference fits:

We recommend heating the head to a minimum of 350° and using nickel based never seize when installing seat(s) with the aid of professional drivers and pilots. We also recommends the use of Liquid nitrogen when production volumes can offset costs.

Web Cam recommends our nickel aluminum bronze seats for maximum performance with titanium valves. The unique alloy blend; 80% copper, 5% nickel, and 10% aluminum, give these seats excellent thermal characteristics, resistance to wear (impact and chemical) and the proper expansion coefficient for use in aluminum heads. For two years we tested and recorded results with titanium valves. In every one of our tests the machinability, thermal conductivity, and resistance to wear of this nickel aluminum bronze material surpassed the high standards we set for success.

It is common in performance builds to use a longer duration cam with more overlap in combination with oversize valves. This combination reduces the valve to valve and valve to piston clearance at overlap. A shorter valve allows the builder to "sink" the valves to regain clearance, without creating excessive valves stem protrusion, poor rocker geometry, and other problems associated with excessive valve stem protrusion.

When guides are installed into a cylinder head, they distort due to interference fit. All our guides are designed with undersized IDs to allow the builder to true the ID and set the desired valve to guide clearance.

Yes. Installed heights and spring pressures are critical to correct operation of the valve train system. Only by confirming the specifications can you be sure of a correct installation. Incorrect installation can result in a catastrophic failure. If you are not certain you have achieved the correct installed height you should contact a qualified professional.